1. Hans Hillen (TPG) Steve Faulkner (TPG) 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 2011 1

2. New Solutions New Problems

3. will be a beautiful thing

4.  What is meant by support? o Features provided o Features implemented o Features implemented with accessibility support In Browsers In Assistive Technology

5.  Features are implemented in browsers o Useful site - When can I use...When can I use  Does not mean features are usable by all users even if they use a browser that ‘supports’ a feature.  Firefox video support Firefox video support

6.  No major browser has full accessibility support for HTML5 video  Providing full accessibility support means jumping through hoops:  Scripted controls  Scripted captioning and audio description

7.  All major browser now support HTML5 video  Meaning you can watch/hear a video and use the controls if you can see, hear and use a mouse

8. Terril ThompsonTerril Thompson: “That all sounds like a lot of work. Isn't HTML5 supposed to be easy?” “Ultimately though... HTML5 is easy. A novice web developer can pop a video onto their web page in less than a minute with some very simple HTML markup. Unfortunately if they do that today it won't be accessible without a little additional sweat. Someday, hopefully, browsers will do all of this work for us, and every video will be accessible. That's what we're working toward.”

9.  All major browser now support HTML5 canvas  Meaning dynamic images, animation, games and content is available without plug-ins

10.  Only one major browser supports HTML5 canvas accessibility  And only partially

11.  The accessibility features of canvas are still being specified.  What is implemented in IE9 gives an idea of how canvas accessibility will work.  Example Example

12.  What’s it mean? o Conveys semantics required to understand and interact. o Can be used in a device independent way o Uses common design patterns o Accomodates browser & OS accessibility features o interoperable

13. Accessibility API role=button action=press state=focused value= search browser Input device

14. roles states properties interaction Accessibility APIs MSAA Iaccessible2 UI automation AX STK + device independent interaction

15. MSAA inspect.32.exe or inspect.exe

16. Aviewer

17.  Accessibility features for a button a whirlwind tourwhirlwind tour

18.  When implemented and implemented accessibly, will make it a lot easier to provide accessible UI’s  Current implementation is patchy and where implemented, accessibility support is poor.  Lets take a quick tour: HTML5 form controlsHTML5 form controls

19.  Minor addition to HTML5  Yet brings new headaches for developers and users o Poor contrast o disappears o Results in different accessible labels across browsers and labelling methods o HTML5 Accessibility Chops: the placeholder attribute HTML5 Accessibility Chops: the placeholder attribute

20.  ARIA defines roles that act as landmarks for intra page navigation and identification of common content areas  HTML5 defines section elements for common semantic features of pages, some old some new  There is some overlap  HTML5 section elements are largely unimplemented (accessible). o FireFox has some experimental implementation

21.  Examples of use o Bruce Lawson’s sitesite o Wordpress Wordpress  Mappings between section elements and landmark roles: o HTML5 Accessibility Chops: section elements HTML5 Accessibility Chops: section elements

22.  Landmark roles identify important sections commonly found in web pages: o Applied to container elements o Allow AT users to quickly see which sections a page has and navigate to individual sections o In JAWS, use the following commands: ; (semicolon):jump to next landmark Shift + ;(semicolon): jump to previous landmark Ctrl + Ins + ;(semicolon): Show list of available landmarks o In NVDA use D to jump to next landmark Shift + D to previous landmark NVDA+f7 Show list of available landmarks

23.  Available Landmark Roles  Banner: A region that contains the primary heading or web site title. (site logo, login details, etc.)  Search: The search tool of a web document.  Navigation: The documents Navigation menus and links.  Main: The main content of web document.  Form: contains a collection of items and objects that, as a whole, combine to create a form.  Complementary: content that has meaning outside the page as well (e.g. a sidebar with related articles).  Contentinfo: Metadata that applies to the parent document (e.g. copy right disclaimers, company info).  Application: See next slide. Using WAI ARIA Landmark Roles

24.  Normally, Screen readers browse in ‘virtual mode’ o Screen reader navigates a virtual copy of the web page. o Screen reader intercepts all keystrokes, and uses them for its own virtual navigation (e.g. ‘H’ for heading navigation).  For dynamic web apps, virtual mode may need to be turned off o Interactive widgets need the keystrokes themselves. o Content needs to be live, not a virtual copy. o Normally, the user had to switch manually between virtual an non-virtual mode.  role=“application” o When applied a container element the screen reader will automatically switch to non virtual mode.

25.  Some parts of your application may actually be treated as a document rather than application UI. For example: o A web based email client has panes in which messages are read or created. o A blog viewer web application can load articles to read.  In these parts, the screen reader user needs virtual mode: o To make use of the special navigation that comes with it. o To be able to read non focusable content  role=“document” o When applied to a container inside an application role, the screen reader will switch back to virtual mode. o Allows documents to be read or edited inside a web app.

26. HTML5Accessibility.com

27. Practical examples 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201127

28. 1. Start with HTML elements o Any HTML element can be extended with ARIA. Examples:,,,,,,, 2. Add a ‘role’ attribute. o Only one role is allowed per element, 3. Add state /properties attributes if applicable. o A single elements can have one or more states o Attribute names always start with ‘aria-’ 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201128

29.  ARIA doesn’t change anything to your widget: o It only provides semantic information for AT o Behavior and styles still need to be provided by developer  Some HTML elements already have a default, ‘native’ role. o e.g. (role = ‘cell’), (role=“link”),, o Native role is always overridden by ARIA role E.g. is announced as a tab by a screen reader rather than a table  Role values generally stay the same, state values can change o Trough user input (event handlers), o elem.setAttribute(‘aria-selected’, ‘false’);  Some roles have required state attributes o E.g. A ‘radio’ role requires the ‘aria-checked’ state  Requirements for an ‘ARIA ready’ widget: Focusable & Keyboard Accessible! 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201129

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31.  To be accessible, ARIA input widgets need focus o Use natively focusable elements, such as,, etc o Add ‘tabindex’ attribute for non focusable elements, such as,, etc. Tabindex=“0”: Element becomes part of the tab order Tabindex=“-1” (Element is not in tab order, but focusable) o For composite widgets (menus, trees, grids, etc.): Every widget should only have 1 stop in the tab order. Keep track where your widget’s current tab stop is: o Alternative for tabindex: ‘aria-activedescendant=“ ” Focus remains on outer container AT perceives element with the specified ID as being focused. You must manually highlight this active element, e.g. With CSS 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201131

32.  Every Widget must be operable by keyboard  Create you own event handlers to manage o For composite widgets (trees, menus, etc.) individual parts can be reached using other keys, such as: Arrow keys Home, End, PgUp, PgDn Enter, Space  Keep in mind: how would I navigate this widget in a desktop environment?  Mouse based actions must also be available through the keyboard. For example: o Write Key handlers trigger the same results mouse events o Use context menus to make relevant options accessible. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201132

33.  Not sure about how a widget should behave with the keyboard? o Use the DHTML Style Guide: o http://dev.aol.com/dhtml_style_guide http://dev.aol.com/dhtml_style_guide 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201133

34.  Make sure that all widgets are reachable through keyboard o Depend on Tab order (default or custom?) o Support global keyboard shortcuts How do you notify your users? o Implementing a custom focus manager Might be best solution for very complex UI's Let go of the traditional tab order idea ("all focusable elements must be reachable by tab order") Provide intuitive skipping mechanisms 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201134

35.  The ability to skip content is crucial for both screen reader and keyboard users  Skip links are out of date, out of fashion and often is misused  Better alternatives for skipping: o Collapsible sections o Consistent shortcuts (e.g. a shortcut that moves focus between panes and dialogs) o Custom focus manager that allows the user to move focus into a container to skip its contents 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201135

36.  More and more web apps use HTML based popup dialogs rather than actual browser windows/dialogs o Get a screen reader to perceive it properly using role="dialog"  Dialogs should have their own tab order o Focus should "wrap"  For modal dialogs, it should not be possible to interact with the main page o Prevent keyboard access o Virtual mode access can't be prevented  For non modal dialogs, provide shortcut to switch between dialog and main page  If dialog supports moving or resizing, these features must be keyboard accessible  Support closing dialogs using Enter (OK) or Escape (Cancel) keys o Focus should be placed back on a logical element, e.g. the button that triggered the dialog. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201136

37.  Trees, Lists, Grids can support single or multiple selection o Multiple selection must be keyboard accessible, for example: Shift + arrow keys: contiguous selection Ctrl + arrow keys: move focus without selection Ctrl + space: Toggle focused item in selection (discontiguous selection)  Editable grids need to support switching to edit mode by keyboard 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201137

38.  You can used ARIA to make your form validation easier to manage. o aria-required & aria-invalid states o Role="alert" to flag validation errors immediately  Use validation summaries with links to make invalid entries easier to find o Role="alertdialog" to mark up the summary  Visual tooltips: Useful for validation messages and formatting instructions o Tooltips must be keyboard accessible o Tooltip text must be associated with the form control using aria- describedby 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201138

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40.  Every widget need some kind of ‘identity’, or ‘label’ that AT can use to announce it to the user: o Singular interactive widgets, e.g. button, checkbox o Composite widgets, such as trees or toolbars: Requires both a label for the widget as a whole and its individual parts o Container widgets: A window or Pane requires a title  To label ARIA widgets: o You could use standard HTML labeling techniques: Label element and title attributes. o Or: Aria-labelledby, aria-label, & aria-describedby 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201140

41.  Aria-labelledby=“IDREFS” o Value is one or more IDs of elements that identifiy the widget. o The elements ‘aria-labelledby’ targets can be any kind of text based element, anywhere in the document. o Add multiple Ids to concatinate label text: Multiple elements can label one widget, and one element can label multiple widgets. (example)  Aria-describedby=“IDREFS” o Similar to labelledby, except used for additional description, e.g. Form hints, instructions, etc.  Aria-label o Simply takes a string to be used as label. o Quick and dirty way of making the screen reader say what you want. o Very easy to use, but only supported in Firefox at the moment. My Folders Each tree item has a context menu with more options... 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201141

42.  Containers such as toolbars, dialogs, and regions provide context for their contents  When the user moves focus into the container, the screen reader should first announce the container before announcing the focused control Confirm Are you sure you want to do that? Yes No 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201142

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44.  Live regions o Parts of a Web page that the author expects to change and where new information maybe added updated or removed. o Examples of live regions: Status updates Changing stock information Chat windows Log windows (chat transcript logs), notification areas (status, alerts) 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201144

45.  Live regions enable assistive technologies (such as screen readers) to inform users of updates.  Without live regions, AT users may not be aware that content elsewhere on the page has changed. o Users miss out on relevant info o Users have to ‘search’ for updated page content  With live regions, updated information is announced automatically.  Example: stock updater 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201145

46.  To identify a live region, add the aria-live attribute.  One of the most important concepts behind live regions is politeness.  Politeness indicates how much priority a live region has.  The following politeness values are available for aria- live: off, polite, and assertive. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201146

47.  Aria-live="off" o Default value, identical to not setting aria-live. Examples: A DHTML clock Number of users currently online  Aria-live=“polite” o Updates are announced but won’t interrupt the user o Should be used in most situations involving live regions that present new information to users: Updates to news headlines, twitter alerts, monitored stocks, etc.  Aria-live=“assertive” o Updates are announced and interrupt what the user is doing Only use for important updates that require immediate attention. Warnings & error notifications. Session timeout notifications 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201147

48.  aria-atomic="true | false" o Optional. Indicates if assistive technology should present all or part of the changed region to the user. aria-atomic=“true”: assistive technology should announce the entire region when part of it changes; aria-atomic=“false”: only the part of the region that changed should be announced on its own.  aria-busy="true | false" o Optional. Indicates whether region has finished updating, or whether certain parts are still expected to change. aria-busy=“true”: region not fully updated yet, AT should wait. aria-busy=“false”: region update is complete, AT can start announcing the update. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201148

49.  Role=“alert” o Used for one-time, high priority notifications. o Should be shown for a period of time, or until the cause of the alert is solved. o Should contain a basic message, no complex content. o The element with the alert role does not need to be focused to be announced. Elements with role=“alert” receive aria-live=“assertive” and aria-atomic=“true” as default values. Screen reader automatically announces the alert text, after saying ‘alert’ o Example: Form validation sample  Role=“alertdialog” o Similar to Alert, but meant for actual (DHTML ) dialog windows. o May contain other widgets, such as buttons or other form fields. o Does require a sub element (such as a ‘confirm’ button) to receive focus. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201149

50.  Role=“status” o Contains advisory information for the user but is not important enough to justify an alert. o Automatically receives aria-live=“polite” o Should not receive focus  Role=“timer” o A numerical counter which indicates an amount of elapsed time from a start point, or the time remaining until an end point. o Should be updated at regular intervals  Role=“marquee” o A type of live region where non-essential information changes frequently E.g. stock tickers, banners  Role=“log” o Like marquee, but information is added in meaningful order and old information may disappear. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201150

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52.  In IE, JAWS currently does not properly announce dialogs when moving focus into them  It's possible to provide a fallback solution for IE to fix this, using hidden fieldsets to apply the ARIA dialog markup to o Hide fieldset's padding, margin, and border o Move legend off-screen Confirm Are you sure you want to do that? Yes No 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201152

53.  Developers often use links as (icon) buttons o Side effect: screen reader will announce them as a link, not a button  This can be made accessible by setting role="button" o Screen reader announces link as button now, but also provides hint for using a button ("press" space to activate) You lie! Links work through the Enter key, Space will scroll down the page o To make sure JAWS is not lying, you'll have to manually add a key event handler for the Space key. refresh 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201153

54.  Sometimes a widget structure is not explicit via the DOM and logical structure of a page.  Aria-owns=“IDREFS” o Indicates that the element(s) referenced by the IDs should be considered a child of the element that has this attribute. Vegetables Carrot Tomato Lettuce … Asparagus 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201154

55.  Some developers will use multiple HTML elements to create one single grid. For example: o One for the header row, one for the body rows o One for every single row  Why? Because this is easier to manage, style, position, drag & drop, etc.  Screen reader does not perceive one single table, but it sees two ore more separate tables o Association between column headers and cells is broken o Screen reader's table navigation is broken 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201155

56.  If using a single table is not feasible, use ARIA to fix the grid structure as perceived by the screen reader o Use role="presentation" to hide the original table elements form the screen readers o Use a combination of "grid", "row", "gridcell", "columnheader" roles to make the screen reader see one big grid. 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201156

57.  Using ARIA to create a correct grid structure Dog Names Cat Names Cow names Fido Whiskers Clarabella 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201157

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59.  To be WCAG 2 compliant, background and foreground colors for text needs to have sufficient contrast  If that's not possible, it's an option to design a high(er) contrast theme that the user can enable 03 / 15 / 1159Accessibility of HTML5 and Rich Internet Applications - CSUN 2011

60.  High Contrast Mode: o Windows OS specific feature, inherited by browser o Background & foreground colors are overridden o Background images are stripped out  Problematic for widgets: o They often use background color and images to indicate information (e.g. icons & selection highlights)  Solution: o Detect whether high contrast mode is active o If so, provide workarounds: Inject html images or text to DOM Add additional visual indications, e.g. font weight, decoration & style 03 / 15 / 1160Accessibility of HTML5 and Rich Internet Applications - CSUN 2011

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63.  To test if your ARIA works: o Use a screen reader to try out your aria widgets and roles. JAWS 10 has decent support, but misses certain things NVDA has better ARIA support, is free and has a ‘silent’ mode Compare with widgets in Desktop to know what to expect.  Using MSAA Tools o Inspect32 quick and effective Shows Focus role, states, name and description o AccExplorer Lets you have a look at your page’s underlying ‘accessible tree  Using Browser Tools o Firebug for firefox o Developer Tools for IE8 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201163

64.  Get Started with ARIA: o http://www.w3.org/WAI/intro/aria http://www.w3.org/WAI/intro/aria  ARIA Best Practices: o http://www.w3.org/TR/wai-aria-practices/ http://www.w3.org/TR/wai-aria-practices/  DHTML Styleguide: o http://dev.aol.com/dhtml_style_guide http://dev.aol.com/dhtml_style_guide 03 / 15 / 11Accessibility of HTML5 and Rich Internet Applications - CSUN 201164